Rotary pump



lPatented Aug. 18, 1925.

I 1,550,286 PATENT omcs.

erro sones, orBsaLIN-scnlcmoar. amm.

normar Porn.

Application led Bbvember 6, 1924. Serial Io, '748,128.

To all whom 'it may concern,.-

'Be it known that I, O'rro Sono civil engineer, a' citizen of the German lepublic, and resident of Berlin-Schmargendo Germany, have invented a new and useful Improved Rotary Pump, of which the followin is a specliication.

y invention relates to rotary pumps having a rotary eccentric'ally arranged bladecarrier carr ing radially movable blades, the outer en faces of which slide along the circumferential inner wall of the casing enclosing said blade-carrier with its blades.

There arises, of course, friction between said end-faces and said inner wall, and the friction is very great in consetplience of the large number of revolutions of t e rotatory bladecarrier and of the centrifugal force arising. Owing to that great friction it is difficult to maintain proper tightness at the said endfaces. In this respect two requirements must be considered. One thereof is that the surface-preure at each blade end-face be only moderate; the other, that each blade endface be continuously in proper contact with the circumferential interior surface of the casing. It is extremely diicult to answer The diiliculties experienced in practical service of this kind are based on the fact Athat a lar e number of revolutions entails a high sli ing-speed of theblade end-faces at the inner casing-wall, and that at the same time the surface-pressure rises considerably in consequence of the strong centrifugal force arising in the blades. I am aware of the fact that endeavors have been made to 'overcome the diiculties with the aid of vsprings 'connected at one end with the blades and atthe other end either with the bladecarrier or with the shaft thereof, but the respectiveconstructions have roved un- Suited for continuous service m that the springs arranged in the manner stated cannot possibly stand the very great incessant changes of the stress to which they are sub-y I ljected while the) ump is inoperation. Matters will be per tly clear. if it is borne in mind'that the number of these. changes of stress amountsannually in average to Say about 150 millions, and that, besides; owing to the narrowness of the chamber or chambers enclosing the said springs, the specific stre of the material of which the springs consists must be a propriately great.

Now, all dii'cu ties experienced and all drawbacks met with are overcome completely by my invention, the gist of which resides in the feature that the springs are arranged Vto extend diametrically from one blade to the diametrically. opposite blade. In other words: two diametrically located blades are connected with one another either by a spring common to them both, or lby two springs which are connected with one another by an intermediate member, for instance a Wire (which/may be integral with' the two springs), the arrangement being always suc that the two blades concerned are connected with one another either by the one spring or b the two springs and their connecting mem r, this latter constructional form'A being practically only immaterially different from the other one. The spring is, or the springs are, under a certain tenslon, generally and preferably tensile stress (although constructional forms are possible in which the spri are subjected to compressive stress) and 1t is a particular and characteristic, as well as a decisive feature from which depends the lastin efficiency of my improved rotary pump, t at the tension of the spring or springs connecting two oppositely located blades with one another remains practicall the same irrespective of the position of t e two blades in their carrier while this is rotating.

The rotatcry carrier need not have only two oppositely located blades, or only one pair ofv blades respectively; there may be,

or instance, two pairs which are located at right angles with respect to one another. I have shown this constructional' form by way of example in the accompanying drawing in which Iigure l is a vertical cross-section through this pump, and Figure 2 a'horizontal section through the blade-carrier and two of the ,oppositely located blades, this figure -being drawn to an enlarged scale.

On the drawing a denotesfthe blades which are radially movable in thegrotatory bladecarrier c which is arranged eccentmcally in the example shown, three springs I) for each y located diametrically opposite to one another 7 form a pair. There are two'su'ch pairs in the example shown. The blades forming a pair are connected with one another by a spring b which consists of two helical parts located within the hollow bladesA and o-f a straight connecting member which is integral with the two helical parts, @r springs proper respectively. There are provided, 1n

pair of blades, but Vthere may be less or more than three springs, as desired or required, and depending 'chiefly upon the axial length of the ump. Thesprings of the other pair Vof bla es extend, of course, at lright angles to those of the first-mention d pair of Blades, but their arrangement relatively to these latter springs is such (Fig. 2) that the straight middle or connecting parts of oneV set lie midway between the straight or connecting parts of the other set so that the two sets do not in the least interfere with one another.

In View of the fact that the eccentricity of the rotatory vblade-carrier relatively to the casing is comparatively slight, the length of any one of the springs b, or of two connected springs b respectively (pertainin lto a pair.

of blades, as described), does not c ange considerably, only slightly. In Fig. 1 the .eccentricity is somewhat exaggerated intentionally in order to vshow that even in this case the length of the spring (or springs) located horizontally at the time being, relatively to the length of the springs located vertically at the time being, is very slight,

in fact, so slight that it can be practically` neglected. It is obvious from this that the tension of the springs changes onl very slightly,rinV fact, extraordinarily s ightly.

, The tension of the springs is so determined circuited rotor.

that the end-faces of the blades a press onl slightly upon the inner circumferential wa l of the casing, while the blade-carrier is rotating with proper speed, just suiiicient to maintain the necessary tightness, the friction being balanced nearly completely by the springs, which are expanded as soon as the rotatory blade-carrier has attained a certain spee When the ump is at rest, the Vblades project either o y a little or not at all over the circumference o f the blade-carrier, in that they are then retained within this latter by the springs. Also this is a very favorable feature in that a pump of this kind can start very easily as it can start without load which is useful especially in the case of the pump being coupled directlywith an electromotor, ftr instance a motor with short- The delivery commences only after a certain number of revolutions has been attained and the blade end-faces have c ome in contact with the inner circumferentlal surface of the caslng. It is obvious that the work of friction is greatly diminished by the arrangement described and by the mode of operation resulting therefrom; the wear and tear of these umps is extraorl dinarily small, and the eigciency is excep-` tionally good. i The pumps can run with the same number of revolutions as have normal electro-motors; it is yno more necessary to employ slow-speed motors which are considerably more expensive than normal ones.

I claim:

1. yA rotary pump, 4comprising,rin combination: a caslng; an eccentrically arranged rotatory blade-carrier therein; radially movable blades arranged diametrically opposite to one another in said carrier; anda sprinvr connectingrsaidy blades with each other an being adapted to counteract the centrifugal force arising inthe said blades whilevthe said carrier rotates.

2.1A rotary pump, comprisingrin combination: a casing; an eccentrically arranged rotatory blade-carrier therein; radially movable blades arranged diametrically opposite y to one another in said carrier; and a helical spring connecting said blades.- with each other and being adapted to counteract the centrifugal force Varising in the said blades while the said carrier rotates.

3. AY rotary pump, comprising, in combination: a. casing; an eccentrically arranged rotatory blade-carrier therein; radially movable blades arranged diametrically opposlte to one another in said carrier; and a spring connecting saidblades directly with each other and being adapted to counteract the centrifugal force .arising Iin the said blades while the said carrier rotates.

4. A rotary pump, comprising, in combination: a casing; an eccentrically arranged rotatory blade-carrier therein; radially movable blades arranged diametrically opposite to one another in said carrier; and a tension-spring connecting said blades with each other and being adapted to counteract the centrifugal force arising `in the said lbladeswhile the said carrier rotates.

5. A rotary pump, comprising, in combination: a casing; an eccentrically arrangedv rotatory blade-carrier therein; hollow, radially movable blades arranged diametrically opposite to one another in said carrier and being closed at their outer ends and open at their inner ends; springs located in said blades and being each connected at one end with a closed blade-end; and a member connecting the opposite springs with one another at their other ends, the connected springs being adapted to counteract the centrifugal force arlsing 'in the said blades while the said carrier rotates.

6. A rotary pumpfcomprising, in' combination: a casing; an eccentrically arranged rotatory blade-carrier therein; pairs of radially movable blades in said carrier, the

blades forming a pair being arranged oppositely to one another; springs connecting the oppositely located blades with one another and being adapted ,to counteractl the centrifugal force arising in the said blades while the said carrier rotates.v

7; A rotary pump, comprising, in combination: a casing; an eccentrically arranged rotatory blade-carrier therein; pairs of radially movable blades in said carrier, the blades forming a pair being arranged oppositely to one another; sprmgsconnecting the ppositely7 located blades with one another and belng adapted to counteract the centrifugal force arising whilethe said carrier rotates, the middle portions of the springs pertaining to one pair of blades being located between the middle portions of the springs pertaining to another pair of blades.

8. A rotarypu'mp, comprisin in combination: a casing; an eccentrica y arranged rotatory. blade-carrier therein; pairs of holy low, radially movable blades in said carrier, theblades being closed at their outer ends and open at their inner ends, andthe blades forming a pair being arranged oppositely to one another; springs located 1n. said blades and being each connected at one end with a closed blade-end; and members connecting the opposite springs with one another at their other' ends, the 'connected springs being adapted to counteract the centriugal force arising while the said carrier rotates, the connecting members of the springs pertaining to one'pair of blades being located between the connecting members pertaining to another pairof blades.

In testimony whereof I aix my signature. p

Y OTTO SORGE.' 

